work on:

 - Create GraphQL resolvers
 - Util function to handle input validation
 - Create local graphql server for testing

Author: roc41d

package-lock.json

@@ -6,20 +6,24 @@
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
     "build": "npx tsc",
-    "start": "tsc src/index.ts"
+    "start": "npx tsc && node dist/index.js"
   },
   "keywords": [],
   "author": "",
   "license": "ISC",
   "devDependencies": {
     "@types/node": "^20.12.11",
+    "serverless-dotenv-plugin": "^6.0.0",
     "ts-node": "^10.9.2",
     "typescript": "^5.4.5"
   },
   "dependencies": {
+    "apollo-server": "^3.13.0",
+    "apollo-server-core": "^3.13.0",
     "apollo-server-lambda": "^3.13.0",
     "dotenv": "^16.4.5",
     "graphql": "^16.8.1",
-    "mongoose": "^8.3.4"
+    "mongoose": "^8.3.4",
+    "node-input-validator": "^4.5.1"
   }
 }

package.json

@@ -1,7 +1,10 @@
 import mongoose from 'mongoose';
 import { ITodo, TodoSchema } from '../models/todo';
+import dotenv from 'dotenv';
 
-const uri = process.env.MONGO_URI ?? '';
+dotenv.config();
+
+const uri = process.env.MONGODB_URI || '';
 
 async function connectDB() {
     try {
@@ -12,7 +15,7 @@ async function connectDB() {
     }
   }
 
-async function getTodos() {
+async function getTodos(): Promise<ITodo[]> {
     try {
         const todos = await TodoSchema.find();
         return todos;
@@ -22,7 +25,7 @@ async function getTodos() {
     }
 }
 
-async function getTodo(id: string) {
+async function getTodo(id: string): Promise<ITodo>{
     try {
         const todo = await TodoSchema.findById(id);
         if (!todo) {
@@ -35,7 +38,7 @@ async function getTodo(id: string) {
     }
 }
 
-async function addTodo(todo: ITodo) {
+async function addTodo(todo: ITodo): Promise<ITodo> {
     try {
         const newTodo = new TodoSchema(todo);
         await newTodo.save();
@@ -46,7 +49,7 @@ async function addTodo(todo: ITodo) {
     }
 }
 
-async function updateTodo(id: string, updateData: Partial<ITodo>) {
+async function updateTodo(id: string, updateData: Partial<ITodo>): Promise<ITodo>{
     try {
         const updatedTodo = await TodoSchema.findByIdAndUpdate(id, updateData, { new: true });
         if (!updatedTodo) {
@@ -59,7 +62,7 @@ async function updateTodo(id: string, updateData: Partial<ITodo>) {
     }
 }
 
-async function deleteTodo(id: string) {
+async function deleteTodo(id: string): Promise<string>{
     try {
         const deletedTodo = await TodoSchema.findByIdAndDelete(id);
         if (!deletedTodo) {

src/database/mongo.ts

@@ -0,0 +1,87 @@
+
+import { ITodo } from '../models/todo';
+import { addTodo, connectDB, deleteTodo, getTodo, getTodos, updateTodo } from '../database/mongo';
+import validateInput from '../utils/validation';
+
+const resolvers = {
+    Query: {
+        todos: async (): Promise<ITodo[]> => {
+            await connectDB();
+            try {
+                const todos = await getTodos();
+                return todos;
+            } catch (error) {
+                console.error('Error fetching todos:', error);
+                throw new Error('Error fetching todos');
+            }
+        },
+        todo: async (_: any, { id }: { id: string }): Promise<ITodo | null> => {
+            await connectDB();
+            try {
+                const validationRules = {
+                    id: 'required|string'
+                };
+                await validateInput({id}, validationRules);
+
+                return await getTodo(id);
+            } catch (error) {
+                console.error('Error fetching todo:', error);
+                throw new Error('Error fetching todo');
+            }
+        },
+    },
+    Mutation: {
+        createTodo: async (_: any, { title, description, completed }: { title: string, description?: string, completed: boolean }): Promise<ITodo> => {
+            await connectDB();
+            try {
+                const validationRules = {
+                    title: 'required|string|minLength:3',
+                    description: 'string',
+                    completed: 'required|boolean',
+                };
+                const newTodo = { title, description, completed } as ITodo;
+
+                await validateInput(newTodo, validationRules);
+
+                return await addTodo(newTodo);
+            } catch (error) {
+                console.error('Error creating todo:', error);
+                throw error;
+            }
+        },
+        updateTodo: async (_: any, { id, title, description, completed }: { id: string, title?: string, description?: string, completed?: boolean }): Promise<ITodo | null> => {
+            await connectDB();
+            try {
+                const validationRules = {
+                    id: 'required|string',
+                    title: 'string|minLength:3',
+                    description: 'string',
+                    completed: 'boolean',
+                };
+                const updateData = { title, description, completed };
+                await validateInput(updateData, validationRules);
+
+                return await updateTodo(id, updateData);
+            } catch (error) {
+                console.error('Error updating todo:', error);
+                throw error;
+            }
+        },
+        deleteTodo: async (_: any, { id }: { id: string }): Promise<string> => {
+            await connectDB();
+            try {
+                const validationRules = {
+                    id: 'required|string'
+                };
+                await validateInput({id}, validationRules);
+
+                return await deleteTodo(id);
+            } catch (error) {
+                console.error('Error deleting todo:', error);
+                throw error;
+            }
+        },
+    },
+};
+
+export default resolvers;

src/graphql/resolvers.ts

@@ -0,0 +1,14 @@
+import resolvers from "./graphql/resolvers";
+import typeDefs from "./graphql/schema";
+
+const { ApolloServer } = require('apollo-server');
+
+const server = new ApolloServer({
+    typeDefs,
+    resolvers,
+});
+
+server.listen().then(({ url }: { url: string }) => {
+
+    console.log(`Server ready at ${url}`);
+});

src/index.ts

@@ -0,0 +1,22 @@
+import { Validator } from 'node-input-validator';
+
+interface ValidationRules {
+    [key: string]: string;
+}
+
+interface InputData {
+    [key: string]: any;
+}
+
+async function validateInput(data: InputData, rules: ValidationRules): Promise<any> {
+    const validator = new Validator(data, rules);
+    const matched = await validator.check();
+
+    if (!matched) {
+        throw new Error(JSON.stringify(validator.errors));
+    }
+
+    return data;
+}
+
+export default validateInput;

src/utils/validation.ts

@@ -26,7 +26,7 @@
 
     /* Modules */
     "module": "commonjs",                                /* Specify what module code is generated. */
-    // "rootDir": "./src",                                  /* Specify the root folder within your source files. */
+    // "rootDir": "./",                                  /* Specify the root folder within your source files. */
     // "moduleResolution": "node10",                     /* Specify how TypeScript looks up a file from a given module specifier. */
     // "baseUrl": "./",                                  /* Specify the base directory to resolve non-relative module names. */
     // "paths": {},                                      /* Specify a set of entries that re-map imports to additional lookup locations. */
@@ -55,7 +55,7 @@
     // "sourceMap": true,                                /* Create source map files for emitted JavaScript files. */
     // "inlineSourceMap": true,                          /* Include sourcemap files inside the emitted JavaScript. */
     // "outFile": "./",                                  /* Specify a file that bundles all outputs into one JavaScript file. If 'declaration' is true, also designates a file that bundles all .d.ts output. */
-    "outDir": "./dist",                                 /* Specify an output folder for all emitted files. */
+    "outDir": "./dist",                                   /* Specify an output folder for all emitted files. */
     // "removeComments": true,                           /* Disable emitting comments. */
     // "noEmit": true,                                   /* Disable emitting files from a compilation. */
     // "importHelpers": true,                            /* Allow importing helper functions from tslib once per project, instead of including them per-file. */